Mercedes-Benz is preparing to wrestle the top spot in the global prestige market away from BMW, surpassing the Volkswagen-owned Audi along the way.

The German carmaker has recorded growth across its global markets this year, increasing sales by 9.7 percent to 610,531 in the first six months of 2011. Its rivals are also on the march however, with BMW growing by 17.8 percent to 689,861 deliveries and Audi by 17.7 percent to 652,970.

"Some of our competitors are now growing faster and more profitably than we are. Granted, those are just snapshots in time and should not be overestimated. After all, many of our best new products are yet to come," the letter reads.

"In the long run we can't be content to be in a 'solid second' or even 'third' place: We are Daimler – we should be far ahead of the pack! And if that requires something that we don't currently have, then we'll identify and develop it," Zetsche added.

In Australia at least, Mercedes is leading the prestige pack, selling 9,872 vehicles for the first six months of 2011 - although this marks a drop from 10,966 for the same period in 2010.

BMW sales in Australia closed at 8461 for the first six months (down from 8785), and Audi wrapped up the first half on 7974 (up from 7225).